Abstract Introduction The benefits of cardiac rehabilitation (CR) in patients with ischaemic cardiomyopathy are well-known. However, inflammatory states have been associated to an increased risk of cardiovascular events. Purpose Evaluate the impact of CR in the serum levels of inflammatory biomarkers and identify potential predictors of that effect. Methods We retrospectively studied consecutive patients with ischaemic cardiomyopathy who completed a CR programme between 2011 and 2017. Patients underwent a supervised exercise training protocol, twice a week during a period of 8 to 12 weeks. Functional capacity was evaluated by metabolic equivalents assessed prior the beginning and 3 months after the programme with a symptom limited exercise treadmill test. Patients without levels of serum C-reactive protein at beginning and at the end of CR programme were excluded. Median variation of serum C-reactive protein was assessed and two groups were defined: one with levels above that and one with levels below. Results Of 250 patients (60.3±11.1 years, 84% male), 67% were admitted after an acute myocardial infarction. Left ventricular ejection fraction ≤40% before CR was present in 32% of individuals. Median levels of serum C-reactive protein before CR were 8.8 (3.1–21.7) mg/L and median variation after CRP was a decrease of 5.1 (0.9–17.7) mg/L (p<0.001). Before CR, higher levels of serum C-reactive protein were seen in obese (15.7 [8–52.7] versus 8.8 [3.2–27.8], p=0.04) and those with higher NT-proBNP (p<0.001). Patients with decrease of >5.1mg/L of serum C-reactive protein had lower prevalence of hypertension (18% versus 30%, p=0.02), higher prevalence of obesity (16% versus 7%, p=0.03), lower levels of HDL cholesterol (38.3 [11.1] versus 43.2 [12.6], p<0.001) and higher levels of NT-proBNP (1079 [610.3–1988] versus 488 [215–777], p<0.001) at baseline. An increase of at least of 10% of functional capacity after CR was reached in 65% of patients, similar between groups. Patients with decrease of serum C-reactive protein >5.1mg/L had also higher reduction of NT-proBNP after CR comparing to baseline (491.1 [142.7–948.5] versus 162.0 [30.9–295.2], p<0.001). Conclusions Serum levels of inflammatory biomarkers decreased after CR in patients with ischaemic cardiomyopathy. Normotension, obesity, lower HDL and higher levels of natriuretic peptides are associated to a better response. Funding Acknowledgement Type of funding sources: None.